Connected Street Lighting: A Strong Foundation for a Smart City

Throughout history, regional and municipal governments have used new technologies to improve the lives of their citizens. The aqueducts of Rome brought water from outside sources into the city, enhancing both public and private facilities. The London Underground, the first underground railway, made it easier and safer for people to move around the burgeoning city. Today, cities are using another new technology, LED lights, to transform the ever-present street lights that line most city streets, dramatically reducing energy use and costs. The impact of LEDs is significant – street lighting can account for up to 50 percent of a city’s entire energy budget. New York estimates it will save $14 million a year in energy costs simply by replacing old lightbulbs with LEDs, while Chicago estimates it will save $10 million.

However, many cities are taking this street light transformation one step further, using IoT-enabled connected street lighting to improve their citizens’ quality of life, increase revenues, cut costs and support the deployment of a range of smart city applications. For example, smart street lighting enables city officials to increase and decrease illumination levels at different times of the day or night in response to weather events. Cities can use it to develop “follow-me” strategies that turn on street lighting only in response to specific pedestrian or vehicle activity, allowing them to reduce their energy costs. Smart street lights enable light flashing and sequencing to support traffic and crowd control during special events. They can also be used to improve safety by increasing lighting in higher-crime areas and providing first responders with the ability to increase lighting when they respond to an incident.

Smart Connectivity: The Spark of True Intelligence

Until recently, cities trying to centralize connectivity for smart street lighting used proprietary gateways that connected to smaller segments of street lights already connected via low-bandwidth communications, such as a power line carrier (PLC) or a local RF mesh network. A cellular modem could also be added for backhaul communications to the central management software platform. However, this proprietary infrastructure was expensive and had limited utility.

With the development of the Internet of Things (IoT), there’s now a much better way. Point-to-point (P2P) cellular technology eliminates the need for proprietary gateways and segment controllers. A wireless cellular modem on each light pole can be configured to support low or high data throughput, depending on the application. A small antenna mounted on the pole enables direct communication to a central management software platform, creating a single network and paving the way for the use of advanced sensors and actuators that enable the deployment of other smart city applications in the future.

Benefits of P2P

P2P technology also delivers a variety of other benefits over previous, proprietary connected street lighting technologies:

Greater coverage, reliability, scalability and efficiency: cellular communications provide reliable connectivity that can scale from very low to high data throughput to support a wide range of applications. Connected street lighting infrastructure providers can scale their solutions to support everything from simple light dimming to more bandwidth-intensive applications such as video surveillance.

Managed network, licensed spectrum: the cellular network is managed by carriers and relies on licensed spectrum, ensuring reliable communication without the interference that hampers other technologies.

Easy installation and maintenance: with cellular technology at the light pole, there is no need for advanced installation expertise, complex initial surveys or ongoing network maintenance. A technician can install the modem at the pole top with minimal commissioning, dramatically reducing field installation costs. Once turned on, the modem immediately connects with the secure, reliable cellular network that’s already in place.

GPS built into the modem: built-in GPS eliminates the need for a separate, standalone GPS device, reducing costs and enabling faster commissioning of light poles.

Open standards: once deployed, connected street light systems should remain operational for decades, whereas systems built using proprietary RF technologies can quickly become obsolete. With cellular public lighting solutions, OEMs can build solutions based on global standards that will be supported for the long-term.

Leveraging Connected Street Lighting Infrastructure for Other Smart City Applications

Once light poles are connected to a central management software platform, regional and municipal governments can use this new intelligent infrastructure as the foundation for other smart city initiatives – all made more efficient and cost effective by taking advantage of these existing assets.

For example, smart city public safety applications can use video surveillance cameras, emergency call stations and environmental monitoring stations (with sensors to detect earthquakes, air quality, noise, etc.) strategically placed on light poles. Digital signage on select street light poles can provide real-time information to drivers, pedestrians and residents related to traffic, emergencies and local events, or be used to generate advertising revenue for the city.

Connected street lighting also enables governments to use their street lights for wi-fi access. These access points can be used by city personnel to lower their cellular data usage, reducing city expenses. Wi-fi access points can also be used to provide internet access to local businesses and residents, providing the city with new sources of leasing or adverting revenues. In addition, cities can use these wi-fi access points to help bridge the digital divide by providing poorer city residents with free or low-cost internet access. Smart parking meters or pay stations connected to light poles can eliminate the costs associated with trenching for standalone meters and pay stations.

Electric vehicle (EV) charging stations can be equipped with payment processing that is integrated with connected lighting in parking lots and near entertainment venues, increasing access for EV drivers, encouraging greater adoption of EVs and generating additional revenue for regional and municipal governments.

Alone, connected street lights using P2P cellular technology offer cities the opportunity to make their city’s lighting more useful, less expensive and smarter. However, connected street lights can also accelerate deployment of wi-fi access points, digital signage, connected parking meters, EV charging stations and other smart city initiatives that allow cities to deliver their citizens a higher quality of life, while also improving city finances. As they move forward with digital transformation, regional and municipal governments should first look at how the IoT enables a seemingly simple technology – the street light – to serve as the foundation for their smart city initiatives.

Regional and municipal governments can Start with Sierra to build more connected, smarter cities. Our recent white paper, The Humble Street Light Shines in Smart City Strategies, provides more detail on how governments can build connected lighting systems that speed the deployment of smart city applications designed to make their cities greener, safer and more efficient.